Escapade!

The air duct is a closed, openable container in the cell. It is scenery and by the window. The description is "The aluminum air duct runs from one wall to another. It's quite large but not set very high, just few centimeters above your head. There's a small [if the air duct is open]opened [end if]grate in the bottom of it."

Understand "silvery/silver" and "vent/vents" and "hatch" and "grate" and "aluminum" as the air duct.

The creature response of the air duct is "'Where does that vent lead?'[paragraph break][c]Oh, it runs through the entire [key castle]castle[endkey castle],[c] [the creature] tells you. [c]And it reaches the outside in several places, of course.[c]"

Instead of discussing with someone about air duct when cousin Herbert is discussable:
try discussing with the noun about cousin herbert.

The guard response of the air duct is "'How do you know I won't just escape through the air duct?' you ask.[paragraph break]'HA HA! I recommend TO NOT try!'".

Instead of eating the air duct:
say "Your teeth aren't strong enough to bite through it.".

Instead of looking under the air duct:
say "The floor is under it.".

Instead of searching the air duct:
say "[if the player carries the light bulb]Searching the duct very carefully, even with the light from the light bulb, yields no results.[otherwise]There's nothing inside.[end if]".

Instead of unlocking the air duct with:
say "It's not locked.".

After opening the air duct:
say "You open the grate on the air duct." instead.

After closing the air duct:
say "You close the grate on the air duct." instead.

Instead of attacking the air duct:
say "There's a small bang when you hit it.".

Instead of touching the air duct:
say "The aluminum feels cold and smooth.".

Instead of pushing, pulling or turning the air duct:
say "It's fixed in place fast. You can't make it budge.".

Instead of listening to the air duct:
say "It doesn't even hum. Maybe it's not on?".

Instead of tasting the air duct:
say "It tastes like aluminum.".

Instead of cutting the air duct:
say "You don't have the tools.".

Instead of climbing the air duct:
say "It's too high to climb on it, and there's not enough space for you between the duct and the ceiling.".

Instead of pouring oil on the air duct:
say "You put some oil into the duct, but it's clearly not enough to make the whole thing slippery enough."